Post-infectious bronchiolitis obliterans(PIBO) is a rare serious chronic lung disease characterized by irreversible small airway fibrosis.Lower respiratory infections are the most common causes in children.Its major clinical characteristics are recurrent or persistent cough, wheezing, shortness of breath, hypoxia, crackles, and persistent for above 6 weeks.Clinical diagnosis mainly depends on clinical manifestations, lung function and high-resolution CT examination.At present, there is no unified standard of treatment, mainly empirical treatment.Most of the children have a poor prognosis, and a small number of children can achieve good results through early diagnosis and intervention.